Highly Corrosion Resistant Aluminum Alloys: Innovative Processing Methods to Enhanced Corrosion Resistance (e.g., layered structures, etc.)

The objective of this proposed Phase II work is to develop a production method for manufacturing rolled plates of a high-strength aircraft aluminum alloy (7075) with high SCC (stress corrosion cracking) resistance. The corrosion resistance is to be improved without a loss in tensile strength. The basic operational processing procedure is to produce aluminum alloy plate through roll bonding of a composite of several layers of standard material such that the grain shape/orientation alternates through the through-thickness plane of the finished plate. It is known from the literature that stress-corrosion cracking will propagate when tensile load is present in the short-transverse direction and to some degree in the long transverse direction. The base period of Phase II will be directed to establish improvements in SCC resistance and strength on plates of laboratory scale. If the Phase II effort is successful, scale-up attempts will take place during the first and second option periods.